Dogs are used for detecting and determining the nature of substances. For example, sniffing dogs are used to detect contraband ranging from fruit, to currency, to drugs and bombs. Sniffing dogs are also used for medical diagnosis purposes, such as for detecting melanoma, bladder cancer, and the onset of epileptic seizures. However, dogs are susceptible to making mistakes, are costly and time consuming to train and maintain, may harbor human communicable diseases, and present other sanitary, safety, and practical problems. Therefore, what is needed and what has been invented is a system and method for identifying a substance, particularly the molecules of a substance.